0049-1800-xxx 326X V.34, V.34-SDC and V.32bis Series Modem – USER’S GUIDE 02/23/2010
Rev. A
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premises.
Phase jitter
The deviation in phase of the transmittal analog signal from its timing signal;
often caused by alternating current components in a telecommunications network.
It is continuous, long-term, and often nearly constant in frequency and severity.
Point-to-point
A line that directly connects two end points (e.g., a remote location to a host
computer); opposite of multipoint.
Port
A connector and associated circuitry enabling digital data to be injected into or
retrieved from a communications network.
Protocol
Formal set of rules governing the format, timing, sequencing, and error control of
exchanged messages on a data network.
PSTN
Public Switched Telephone Network.
PTT
Postal Telegraph and Telephone. Government authority (in many European
companies) that typically operates the public telecommunications network, sets
standards and policies, and negotiates communications issues internationally for a
particular country.
QAM
Quadrature Amplitude Modulation. A type of modulation that varies both the
phase and amplitude of an analog wave.
RS-232-D
See EIA/TIA 232-D.
RTS
Request To Send. The signal from a terminal to its co-located modem that
prepares the modem for data transmission.
SDC
See Synchronous Data Compression.
SDLC
Synchronous data link control; bit-oriented protocol developed by IBM.
Start bit
A data bit used in asynchronous transmission to signal the beginning of a
character.
Stop bit
A data bit used in asynchronous transmission to signal the end of a character.
STX
Start of text control character. Designates the start of a message’s text as well as
(usually) the end of the message heading.
